ETH Price: $2,534.93 (-0.17%)

Transaction Decoder

Block:
20097029 at Jun-15-2024 11:55:23 AM +UTC
Transaction Fee:
0.000189801137812772 ETH $0.48
Gas Used:
51,187 Gas / 3.707994956 Gwei

Emitted Events:

187 UUPSProxy.0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925( 0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925, 0x000000000000000000000000f822d3a2e3af2aeb71ebc2659aa36bd45d8ea331, 0x000000000000000000000000917cee801a67f933f2e6b33fc0cd1ed2d5909d88, 00000000000000000000000000000000000000000000000000354a6ba7a18000 )

Account State Difference:

  Address   Before After State Difference Code
3.312626778562388594 Eth3.312631897262388594 Eth0.0000051187
0x35fA1647...9B6118ac2
0xf822d3a2...45d8Ea331
0.024291641570293523 Eth
Nonce: 216
0.024101840432480751 Eth
Nonce: 217
0.000189801137812772

Execution Trace

UUPSProxy.095ea7b3( )
  • EETH.approve( _spender=0x917ceE801a67f933F2e6b33fC0cD1ED2d5909D88, _amount=15000000000000000 ) => ( True )
    File 1 of 2: UUPSProxy
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.13;
    import "@openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol";
    contract UUPSProxy is ERC1967Proxy {
        constructor(
            address _implementation,
            bytes memory _data
        ) ERC1967Proxy(_implementation, _data) {}
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (proxy/ERC1967/ERC1967Proxy.sol)
    pragma solidity ^0.8.0;
    import "../Proxy.sol";
    import "./ERC1967Upgrade.sol";
    /**
     * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
     * implementation address that can be changed. This address is stored in storage in the location specified by
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
     * implementation behind the proxy.
     */
    contract ERC1967Proxy is Proxy, ERC1967Upgrade {
        /**
         * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
         *
         * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
         * function call, and allows initializing the storage of the proxy like a Solidity constructor.
         */
        constructor(address _logic, bytes memory _data) payable {
            _upgradeToAndCall(_logic, _data, false);
        }
        /**
         * @dev Returns the current implementation address.
         */
        function _implementation() internal view virtual override returns (address impl) {
            return ERC1967Upgrade._getImplementation();
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.6.0) (proxy/Proxy.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
     * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
     * be specified by overriding the virtual {_implementation} function.
     *
     * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
     * different contract through the {_delegate} function.
     *
     * The success and return data of the delegated call will be returned back to the caller of the proxy.
     */
    abstract contract Proxy {
        /**
         * @dev Delegates the current call to `implementation`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _delegate(address implementation) internal virtual {
            assembly {
                // Copy msg.data. We take full control of memory in this inline assembly
                // block because it will not return to Solidity code. We overwrite the
                // Solidity scratch pad at memory position 0.
                calldatacopy(0, 0, calldatasize())
                // Call the implementation.
                // out and outsize are 0 because we don't know the size yet.
                let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                // Copy the returned data.
                returndatacopy(0, 0, returndatasize())
                switch result
                // delegatecall returns 0 on error.
                case 0 {
                    revert(0, returndatasize())
                }
                default {
                    return(0, returndatasize())
                }
            }
        }
        /**
         * @dev This is a virtual function that should be overridden so it returns the address to which the fallback function
         * and {_fallback} should delegate.
         */
        function _implementation() internal view virtual returns (address);
        /**
         * @dev Delegates the current call to the address returned by `_implementation()`.
         *
         * This function does not return to its internal call site, it will return directly to the external caller.
         */
        function _fallback() internal virtual {
            _beforeFallback();
            _delegate(_implementation());
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
         * function in the contract matches the call data.
         */
        fallback() external payable virtual {
            _fallback();
        }
        /**
         * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
         * is empty.
         */
        receive() external payable virtual {
            _fallback();
        }
        /**
         * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
         * call, or as part of the Solidity `fallback` or `receive` functions.
         *
         * If overridden should call `super._beforeFallback()`.
         */
        function _beforeFallback() internal virtual {}
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
    pragma solidity ^0.8.2;
    import "../beacon/IBeacon.sol";
    import "../../interfaces/draft-IERC1822.sol";
    import "../../utils/Address.sol";
    import "../../utils/StorageSlot.sol";
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     *
     * @custom:oz-upgrades-unsafe-allow delegatecall
     */
    abstract contract ERC1967Upgrade {
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(newImplementation, data);
            }
        }
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallUUPS(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            // Upgrades from old implementations will perform a rollback test. This test requires the new
            // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
            // this special case will break upgrade paths from old UUPS implementation to new ones.
            if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
                _setImplementation(newImplementation);
            } else {
                try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                    require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                } catch {
                    revert("ERC1967Upgrade: new implementation is not UUPS");
                }
                _upgradeToAndCall(newImplementation, data, forceCall);
            }
        }
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
        /**
         * @dev Emitted when the beacon is upgraded.
         */
        event BeaconUpgraded(address indexed beacon);
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
        }
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                Address.isContract(IBeacon(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(
            address newBeacon,
            bytes memory data,
            bool forceCall
        ) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeacon {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
     * proxy whose upgrades are fully controlled by the current implementation.
     */
    interface IERC1822Proxiable {
        /**
         * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
         * address.
         *
         * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
         * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
         * function revert if invoked through a proxy.
         */
        function proxiableUUID() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
    pragma solidity ^0.8.1;
    /**
     * @dev Collection of functions related to the address type
     */
    library Address {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         *
         * [IMPORTANT]
         * ====
         * You shouldn't rely on `isContract` to protect against flash loan attacks!
         *
         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
         * constructor.
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize/address.code.length, which returns 0
            // for contracts in construction, since the code is only stored at the end
            // of the constructor execution.
            return account.code.length > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResultFromTarget(target, success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResultFromTarget(target, success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionDelegateCall(target, data, "Address: low-level delegate call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function functionDelegateCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return verifyCallResultFromTarget(target, success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
         * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
         *
         * _Available since v4.8._
         */
        function verifyCallResultFromTarget(
            address target,
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            if (success) {
                if (returndata.length == 0) {
                    // only check isContract if the call was successful and the return data is empty
                    // otherwise we already know that it was a contract
                    require(isContract(target), "Address: call to non-contract");
                }
                return returndata;
            } else {
                _revert(returndata, errorMessage);
            }
        }
        /**
         * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason or using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                _revert(returndata, errorMessage);
            }
        }
        function _revert(bytes memory returndata, string memory errorMessage) private pure {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
     */
    library StorageSlot {
        struct AddressSlot {
            address value;
        }
        struct BooleanSlot {
            bool value;
        }
        struct Bytes32Slot {
            bytes32 value;
        }
        struct Uint256Slot {
            uint256 value;
        }
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    }
    

    File 2 of 2: EETH
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.13;
    import "@openzeppelin-upgradeable/contracts/token/ERC20/IERC20Upgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/proxy/utils/UUPSUpgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/access/OwnableUpgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/utils/cryptography/EIP712Upgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/utils/CountersUpgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/token/ERC20/extensions/draft-IERC20PermitUpgradeable.sol";
    import "@openzeppelin-upgradeable/contracts/utils/cryptography/ECDSAUpgradeable.sol";
    import "./interfaces/IeETH.sol";
    import "./interfaces/ILiquidityPool.sol";
    contract EETH is IERC20Upgradeable, UUPSUpgradeable, OwnableUpgradeable, IERC20PermitUpgradeable, IeETH {
        using CountersUpgradeable for CountersUpgradeable.Counter;
        ILiquidityPool public liquidityPool;
        uint256 public totalShares;
        mapping (address => uint256) public shares;
        mapping (address => mapping (address => uint256)) public allowances;
        mapping (address => CountersUpgradeable.Counter) private _nonces;
        bytes32 private constant _PERMIT_TYPEHASH = keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
        // Cache the domain separator as an immutable value, but also store the chain id that it corresponds to, in order to
        // invalidate the cached domain separator if the chain id changes.
        bytes32 private immutable _CACHED_DOMAIN_SEPARATOR;
        uint256 private immutable _CACHED_CHAIN_ID;
        address private immutable _CACHED_THIS;
        bytes32 private immutable _HASHED_NAME;
        bytes32 private immutable _HASHED_VERSION;
        bytes32 private immutable _TYPE_HASH;
        event TransferShares( address indexed from, address indexed to, uint256 sharesValue);
        // TODO: Figure our what `name` and `version` are for
        constructor() { 
            bytes32 hashedName = keccak256("EETH");
            bytes32 hashedVersion = keccak256("1");
            bytes32 typeHash = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
            _HASHED_NAME = hashedName;
            _HASHED_VERSION = hashedVersion;
            _CACHED_CHAIN_ID = block.chainid;
            _CACHED_DOMAIN_SEPARATOR = _buildDomainSeparator(typeHash, hashedName, hashedVersion);
            _CACHED_THIS = address(this);
            _TYPE_HASH = typeHash;
            _disableInitializers(); 
        }
        function initialize(address _liquidityPool) external initializer {
            require(_liquidityPool != address(0), "No zero addresses");
            
            __UUPSUpgradeable_init();
            __Ownable_init();
            liquidityPool = ILiquidityPool(_liquidityPool);
        }
        function mintShares(address _user, uint256 _share) external onlyPoolContract {
            shares[_user] += _share;
            totalShares += _share;
            emit Transfer(address(0), _user, liquidityPool.amountForShare(_share));
            emit TransferShares(address(0), _user, _share);
        }
        function burnShares(address _user, uint256 _share) external {
            require(msg.sender == address(liquidityPool) || msg.sender == _user, "Incorrect Caller");
            require(shares[_user] >= _share, "BURN_AMOUNT_EXCEEDS_BALANCE");
            shares[_user] -= _share;
            totalShares -= _share;
            emit Transfer(_user, address(0), liquidityPool.amountForShare(_share));
            emit TransferShares(_user, address(0), _share);
        }
        function transfer(address _recipient, uint256 _amount) external override(IeETH, IERC20Upgradeable) returns (bool) {
            _transfer(msg.sender, _recipient, _amount);
            return true;
        }
        function allowance(address _owner, address _spender) public view returns (uint256) {
            return allowances[_owner][_spender];
        }
        function approve(address _spender, uint256 _amount) external override(IeETH, IERC20Upgradeable) returns (bool) {
            _approve(msg.sender, _spender, _amount);
            return true;
        }
        function increaseAllowance(address _spender, uint256 _increaseAmount) external returns (bool) {
            address owner = msg.sender;
            uint256 currentAllowance = allowance(owner, _spender);
            _approve(owner, _spender,currentAllowance + _increaseAmount);
            return true;
        }
        function decreaseAllowance(address _spender, uint256 _decreaseAmount) external returns (bool) {
            address owner = msg.sender;
            uint256 currentAllowance = allowance(owner, _spender);
            require(currentAllowance >= _decreaseAmount, "ERC20: decreased allowance below zero");
            unchecked {
                _approve(owner, _spender, currentAllowance - _decreaseAmount);
            }
            return true;
        }
        function transferFrom(address _sender, address _recipient, uint256 _amount) external override(IeETH, IERC20Upgradeable) returns (bool) {
            uint256 currentAllowance = allowances[_sender][msg.sender];
            require(currentAllowance >= _amount, "TRANSFER_AMOUNT_EXCEEDS_ALLOWANCE");
            unchecked {
                _approve(_sender, msg.sender, currentAllowance - _amount);
            }
            _transfer(_sender, _recipient, _amount);
            return true;
        }
        function permit(
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) public virtual override(IeETH, IERC20PermitUpgradeable) {
            require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
            bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
            bytes32 hash = _hashTypedDataV4(structHash);
            address signer = ECDSAUpgradeable.recover(hash, v, r, s);
            require(signer == owner, "ERC20Permit: invalid signature");
            _approve(owner, spender, value);
        }
        // [INTERNAL FUNCTIONS] 
        function _transfer(address _sender, address _recipient, uint256 _amount) internal {
            uint256 _sharesToTransfer = liquidityPool.sharesForAmount(_amount);
            _transferShares(_sender, _recipient, _sharesToTransfer);
            emit Transfer(_sender, _recipient, _amount);
        }
        function _approve(address _owner, address _spender, uint256 _amount) internal {
            require(_owner != address(0), "APPROVE_FROM_ZERO_ADDRESS");
            require(_spender != address(0), "APPROVE_TO_ZERO_ADDRESS");
            allowances[_owner][_spender] = _amount;
            emit Approval(_owner, _spender, _amount);
        }
        function _transferShares(address _sender, address _recipient, uint256 _sharesAmount) internal {
            require(_sender != address(0), "TRANSFER_FROM_THE_ZERO_ADDRESS");
            require(_recipient != address(0), "TRANSFER_TO_THE_ZERO_ADDRESS");
            require(_sharesAmount <= shares[_sender], "TRANSFER_AMOUNT_EXCEEDS_BALANCE");
            shares[_sender] -= _sharesAmount;
            shares[_recipient] += _sharesAmount;
            emit TransferShares(_sender, _recipient, _sharesAmount);
        }
        function _authorizeUpgrade(
            address newImplementation
        ) internal override onlyOwner {}
        function _useNonce(address owner) internal virtual returns (uint256 current) {
            CountersUpgradeable.Counter storage nonce = _nonces[owner];
            current = nonce.current();
            nonce.increment();
        }
        // [GETTERS]
        function name() public pure returns (string memory) { return "ether.fi ETH"; }
        function symbol() public pure returns (string memory) { return "eETH"; }
        function decimals() public pure returns (uint8) { return 18; }
        function totalSupply() public view returns (uint256) {
            return liquidityPool.getTotalPooledEther();
        }
        function balanceOf(address _user) public view override(IeETH, IERC20Upgradeable) returns (uint256) {
            return liquidityPool.getTotalEtherClaimOf(_user);
        }
        function getImplementation() external view returns (address) {
            return _getImplementation();
        }
        function nonces(address owner) public view virtual override returns (uint256) {
            return _nonces[owner].current();
        }
        function DOMAIN_SEPARATOR() external view override returns (bytes32) {
            return _domainSeparatorV4();
        }
        function _domainSeparatorV4() internal view returns (bytes32) {
            if (address(this) == _CACHED_THIS && block.chainid == _CACHED_CHAIN_ID) {
                return _CACHED_DOMAIN_SEPARATOR;
            } else {
                return _buildDomainSeparator(_TYPE_HASH, _HASHED_NAME, _HASHED_VERSION);
            }
        }
        function _buildDomainSeparator(
            bytes32 typeHash,
            bytes32 nameHash,
            bytes32 versionHash
        ) private view returns (bytes32) {
            return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
        }
        function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
            return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
        }
        // [MODIFIERS]
        modifier onlyPoolContract() {
            require(msg.sender == address(liquidityPool), "Only pool contract function");
            _;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20Upgradeable {
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
        /**
         * @dev Moves `amount` tokens from the caller's account to `to`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address to, uint256 amount) external returns (bool);
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
        /**
         * @dev Moves `amount` tokens from `from` to `to` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address from,
            address to,
            uint256 amount
        ) external returns (bool);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (proxy/utils/UUPSUpgradeable.sol)
    pragma solidity ^0.8.0;
    import "../../interfaces/draft-IERC1822Upgradeable.sol";
    import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
    import "./Initializable.sol";
    /**
     * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
     * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
     *
     * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
     * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
     * `UUPSUpgradeable` with a custom implementation of upgrades.
     *
     * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
     *
     * _Available since v4.1._
     */
    abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
        function __UUPSUpgradeable_init() internal onlyInitializing {
        }
        function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
        }
        /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
        address private immutable __self = address(this);
        /**
         * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
         * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
         * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
         * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
         * fail.
         */
        modifier onlyProxy() {
            require(address(this) != __self, "Function must be called through delegatecall");
            require(_getImplementation() == __self, "Function must be called through active proxy");
            _;
        }
        /**
         * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
         * callable on the implementing contract but not through proxies.
         */
        modifier notDelegated() {
            require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
            _;
        }
        /**
         * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
         * implementation. It is used to validate the implementation's compatibility when performing an upgrade.
         *
         * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
         * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
         * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
         */
        function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
            return _IMPLEMENTATION_SLOT;
        }
        /**
         * @dev Upgrade the implementation of the proxy to `newImplementation`.
         *
         * Calls {_authorizeUpgrade}.
         *
         * Emits an {Upgraded} event.
         */
        function upgradeTo(address newImplementation) external virtual onlyProxy {
            _authorizeUpgrade(newImplementation);
            _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
        }
        /**
         * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
         * encoded in `data`.
         *
         * Calls {_authorizeUpgrade}.
         *
         * Emits an {Upgraded} event.
         */
        function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
            _authorizeUpgrade(newImplementation);
            _upgradeToAndCallUUPS(newImplementation, data, true);
        }
        /**
         * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
         * {upgradeTo} and {upgradeToAndCall}.
         *
         * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
         *
         * ```solidity
         * function _authorizeUpgrade(address) internal override onlyOwner {}
         * ```
         */
        function _authorizeUpgrade(address newImplementation) internal virtual;
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (access/Ownable.sol)
    pragma solidity ^0.8.0;
    import "../utils/ContextUpgradeable.sol";
    import "../proxy/utils/Initializable.sol";
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
        address private _owner;
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        function __Ownable_init() internal onlyInitializing {
            __Ownable_init_unchained();
        }
        function __Ownable_init_unchained() internal onlyInitializing {
            _transferOwnership(_msgSender());
        }
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            _checkOwner();
            _;
        }
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
        /**
         * @dev Throws if the sender is not the owner.
         */
        function _checkOwner() internal view virtual {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
        }
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _transferOwnership(address(0));
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _transferOwnership(newOwner);
        }
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Internal function without access restriction.
         */
        function _transferOwnership(address newOwner) internal virtual {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[49] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/EIP712.sol)
    pragma solidity ^0.8.0;
    import "./ECDSAUpgradeable.sol";
    import "../../proxy/utils/Initializable.sol";
    /**
     * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
     *
     * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
     * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
     * they need in their contracts using a combination of `abi.encode` and `keccak256`.
     *
     * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
     * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
     * ({_hashTypedDataV4}).
     *
     * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
     * the chain id to protect against replay attacks on an eventual fork of the chain.
     *
     * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
     * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
     *
     * _Available since v3.4._
     *
     * @custom:storage-size 52
     */
    abstract contract EIP712Upgradeable is Initializable {
        /* solhint-disable var-name-mixedcase */
        bytes32 private _HASHED_NAME;
        bytes32 private _HASHED_VERSION;
        bytes32 private constant _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
        /* solhint-enable var-name-mixedcase */
        /**
         * @dev Initializes the domain separator and parameter caches.
         *
         * The meaning of `name` and `version` is specified in
         * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
         *
         * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
         * - `version`: the current major version of the signing domain.
         *
         * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
         * contract upgrade].
         */
        function __EIP712_init(string memory name, string memory version) internal onlyInitializing {
            __EIP712_init_unchained(name, version);
        }
        function __EIP712_init_unchained(string memory name, string memory version) internal onlyInitializing {
            bytes32 hashedName = keccak256(bytes(name));
            bytes32 hashedVersion = keccak256(bytes(version));
            _HASHED_NAME = hashedName;
            _HASHED_VERSION = hashedVersion;
        }
        /**
         * @dev Returns the domain separator for the current chain.
         */
        function _domainSeparatorV4() internal view returns (bytes32) {
            return _buildDomainSeparator(_TYPE_HASH, _EIP712NameHash(), _EIP712VersionHash());
        }
        function _buildDomainSeparator(
            bytes32 typeHash,
            bytes32 nameHash,
            bytes32 versionHash
        ) private view returns (bytes32) {
            return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
        }
        /**
         * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
         * function returns the hash of the fully encoded EIP712 message for this domain.
         *
         * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
         *
         * ```solidity
         * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
         *     keccak256("Mail(address to,string contents)"),
         *     mailTo,
         *     keccak256(bytes(mailContents))
         * )));
         * address signer = ECDSA.recover(digest, signature);
         * ```
         */
        function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
            return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
        }
        /**
         * @dev The hash of the name parameter for the EIP712 domain.
         *
         * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
         * are a concern.
         */
        function _EIP712NameHash() internal virtual view returns (bytes32) {
            return _HASHED_NAME;
        }
        /**
         * @dev The hash of the version parameter for the EIP712 domain.
         *
         * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
         * are a concern.
         */
        function _EIP712VersionHash() internal virtual view returns (bytes32) {
            return _HASHED_VERSION;
        }
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
    pragma solidity ^0.8.0;
    /**
     * @title Counters
     * @author Matt Condon (@shrugs)
     * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
     * of elements in a mapping, issuing ERC721 ids, or counting request ids.
     *
     * Include with `using Counters for Counters.Counter;`
     */
    library CountersUpgradeable {
        struct Counter {
            // This variable should never be directly accessed by users of the library: interactions must be restricted to
            // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
            // this feature: see https://github.com/ethereum/solidity/issues/4637
            uint256 _value; // default: 0
        }
        function current(Counter storage counter) internal view returns (uint256) {
            return counter._value;
        }
        function increment(Counter storage counter) internal {
            unchecked {
                counter._value += 1;
            }
        }
        function decrement(Counter storage counter) internal {
            uint256 value = counter._value;
            require(value > 0, "Counter: decrement overflow");
            unchecked {
                counter._value = value - 1;
            }
        }
        function reset(Counter storage counter) internal {
            counter._value = 0;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
     * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
     *
     * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
     * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
     * need to send a transaction, and thus is not required to hold Ether at all.
     */
    interface IERC20PermitUpgradeable {
        /**
         * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
         * given ``owner``'s signed approval.
         *
         * IMPORTANT: The same issues {IERC20-approve} has related to transaction
         * ordering also apply here.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `deadline` must be a timestamp in the future.
         * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
         * over the EIP712-formatted function arguments.
         * - the signature must use ``owner``'s current nonce (see {nonces}).
         *
         * For more information on the signature format, see the
         * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
         * section].
         */
        function permit(
            address owner,
            address spender,
            uint256 value,
            uint256 deadline,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) external;
        /**
         * @dev Returns the current nonce for `owner`. This value must be
         * included whenever a signature is generated for {permit}.
         *
         * Every successful call to {permit} increases ``owner``'s nonce by one. This
         * prevents a signature from being used multiple times.
         */
        function nonces(address owner) external view returns (uint256);
        /**
         * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
         */
        // solhint-disable-next-line func-name-mixedcase
        function DOMAIN_SEPARATOR() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/ECDSA.sol)
    pragma solidity ^0.8.0;
    import "../StringsUpgradeable.sol";
    /**
     * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
     *
     * These functions can be used to verify that a message was signed by the holder
     * of the private keys of a given address.
     */
    library ECDSAUpgradeable {
        enum RecoverError {
            NoError,
            InvalidSignature,
            InvalidSignatureLength,
            InvalidSignatureS,
            InvalidSignatureV // Deprecated in v4.8
        }
        function _throwError(RecoverError error) private pure {
            if (error == RecoverError.NoError) {
                return; // no error: do nothing
            } else if (error == RecoverError.InvalidSignature) {
                revert("ECDSA: invalid signature");
            } else if (error == RecoverError.InvalidSignatureLength) {
                revert("ECDSA: invalid signature length");
            } else if (error == RecoverError.InvalidSignatureS) {
                revert("ECDSA: invalid signature 's' value");
            }
        }
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature` or error string. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {toEthSignedMessageHash} on it.
         *
         * Documentation for signature generation:
         * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
         * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
         *
         * _Available since v4.3._
         */
        function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
            if (signature.length == 65) {
                bytes32 r;
                bytes32 s;
                uint8 v;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                /// @solidity memory-safe-assembly
                assembly {
                    r := mload(add(signature, 0x20))
                    s := mload(add(signature, 0x40))
                    v := byte(0, mload(add(signature, 0x60)))
                }
                return tryRecover(hash, v, r, s);
            } else {
                return (address(0), RecoverError.InvalidSignatureLength);
            }
        }
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature`. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {toEthSignedMessageHash} on it.
         */
        function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, signature);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
         *
         * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
         *
         * _Available since v4.3._
         */
        function tryRecover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address, RecoverError) {
            bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
            uint8 v = uint8((uint256(vs) >> 255) + 27);
            return tryRecover(hash, v, r, s);
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
         *
         * _Available since v4.2._
         */
        function recover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, r, vs);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
         * `r` and `s` signature fields separately.
         *
         * _Available since v4.3._
         */
        function tryRecover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address, RecoverError) {
            // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
            // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
            // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
            // signatures from current libraries generate a unique signature with an s-value in the lower half order.
            //
            // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
            // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
            // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
            // these malleable signatures as well.
            if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                return (address(0), RecoverError.InvalidSignatureS);
            }
            // If the signature is valid (and not malleable), return the signer address
            address signer = ecrecover(hash, v, r, s);
            if (signer == address(0)) {
                return (address(0), RecoverError.InvalidSignature);
            }
            return (signer, RecoverError.NoError);
        }
        /**
         * @dev Overload of {ECDSA-recover} that receives the `v`,
         * `r` and `s` signature fields separately.
         */
        function recover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address) {
            (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
            _throwError(error);
            return recovered;
        }
        /**
         * @dev Returns an Ethereum Signed Message, created from a `hash`. This
         * produces hash corresponding to the one signed with the
         * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
         * JSON-RPC method as part of EIP-191.
         *
         * See {recover}.
         */
        function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
            // 32 is the length in bytes of hash,
            // enforced by the type signature above
            return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
    32", hash));
        }
        /**
         * @dev Returns an Ethereum Signed Message, created from `s`. This
         * produces hash corresponding to the one signed with the
         * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
         * JSON-RPC method as part of EIP-191.
         *
         * See {recover}.
         */
        function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
            return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
    ", StringsUpgradeable.toString(s.length), s));
        }
        /**
         * @dev Returns an Ethereum Signed Typed Data, created from a
         * `domainSeparator` and a `structHash`. This produces hash corresponding
         * to the one signed with the
         * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
         * JSON-RPC method as part of EIP-712.
         *
         * See {recover}.
         */
        function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
            return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.13;
    interface IeETH {
        function name() external pure returns (string memory);
        function symbol() external pure returns (string memory);
        function decimals() external pure returns (uint8);
        function totalShares() external view returns (uint256);
        function shares(address _user) external view returns (uint256);
        function balanceOf(address _user) external view returns (uint256);
        function initialize(address _liquidityPool) external;
        function mintShares(address _user, uint256 _share) external;
        function burnShares(address _user, uint256 _share) external;
        function transferFrom(address _sender, address _recipient, uint256 _amount) external returns (bool);
        function transfer(address _recipient, uint256 _amount) external returns (bool);
        function approve(address _spender, uint256 _amount) external returns (bool);
        function increaseAllowance(address _spender, uint256 _increaseAmount) external returns (bool);
        function decreaseAllowance(address _spender, uint256 _decreaseAmount) external returns (bool);
        function permit(address owner, address spender, uint256 value, uint256 deadline, uint8 v, bytes32 r, bytes32 s) external;
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.13;
    import "./IStakingManager.sol";
    interface ILiquidityPool {
        struct PermitInput {
            uint256 value;
            uint256 deadline;
            uint8 v;
            bytes32 r;
            bytes32 s;
        } 
        enum SourceOfFunds {
            UNDEFINED,
            EETH,
            ETHER_FAN,
            DELEGATED_STAKING
        }
        struct FundStatistics {
            uint32 numberOfValidators;
            uint32 targetWeight;
        }
        // Necessary to preserve "statelessness" of dutyForWeek().
        // Handles case where new users join/leave holder list during an active slot
        struct HoldersUpdate {
            uint32 timestamp;
            uint32 startOfSlotNumOwners;
        }
        struct BnftHolder {
            address holder;
            uint32 timestamp;
        }
        struct BnftHoldersIndex {
            bool registered;
            uint32 index;
        }
        function initialize(address _eEthAddress, address _stakingManagerAddress, address _nodesManagerAddress, address _membershipManagerAddress, address _tNftAddress) external;
        function numPendingDeposits() external view returns (uint32);
        function totalValueOutOfLp() external view returns (uint128);
        function totalValueInLp() external view returns (uint128);
        function getTotalEtherClaimOf(address _user) external view returns (uint256);
        function getTotalPooledEther() external view returns (uint256);
        function sharesForAmount(uint256 _amount) external view returns (uint256);
        function sharesForWithdrawalAmount(uint256 _amount) external view returns (uint256);
        function amountForShare(uint256 _share) external view returns (uint256);
        function deposit() external payable returns (uint256);
        function deposit(address _referral) external payable returns (uint256);
        function deposit(address _user, address _referral) external payable returns (uint256);
        function withdraw(address _recipient, uint256 _amount) external returns (uint256);
        function requestWithdraw(address recipient, uint256 amount) external returns (uint256);
        function requestWithdrawWithPermit(address _owner, uint256 _amount, PermitInput calldata _permit) external returns (uint256);
        function requestMembershipNFTWithdraw(address recipient, uint256 amount, uint256 fee) external returns (uint256);
        function batchDepositAsBnftHolder(uint256[] calldata _candidateBidIds, uint256 _numberOfValidators) external payable returns (uint256[] memory);
        function batchRegisterAsBnftHolder(bytes32 _depositRoot, uint256[] calldata _validatorIds, IStakingManager.DepositData[] calldata _registerValidatorDepositData, bytes32[] calldata _depositDataRootApproval, bytes[] calldata _signaturesForApprovalDeposit) external;
        function batchApproveRegistration(uint256[] memory _validatorIds, bytes[] calldata _pubKey, bytes[] calldata _signature) external;
        function batchCancelDeposit(uint256[] calldata _validatorIds) external;
        function sendExitRequests(uint256[] calldata _validatorIds) external;
        function rebase(int128 _accruedRewards) external;
        function addEthAmountLockedForWithdrawal(uint128 _amount) external;
        
        function setStakingTargetWeights(uint32 _eEthWeight, uint32 _etherFanWeight) external;
        function updateAdmin(address _newAdmin, bool _isAdmin) external;
        function pauseContract() external;
        function unPauseContract() external;
        
        function decreaseSourceOfFundsValidators(uint32 numberOfEethValidators, uint32 numberOfEtherFanValidators) external;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
     * proxy whose upgrades are fully controlled by the current implementation.
     */
    interface IERC1822ProxiableUpgradeable {
        /**
         * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
         * address.
         *
         * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
         * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
         * function revert if invoked through a proxy.
         */
        function proxiableUUID() external view returns (bytes32);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
    pragma solidity ^0.8.2;
    import "../beacon/IBeaconUpgradeable.sol";
    import "../../interfaces/draft-IERC1822Upgradeable.sol";
    import "../../utils/AddressUpgradeable.sol";
    import "../../utils/StorageSlotUpgradeable.sol";
    import "../utils/Initializable.sol";
    /**
     * @dev This abstract contract provides getters and event emitting update functions for
     * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
     *
     * _Available since v4.1._
     *
     * @custom:oz-upgrades-unsafe-allow delegatecall
     */
    abstract contract ERC1967UpgradeUpgradeable is Initializable {
        function __ERC1967Upgrade_init() internal onlyInitializing {
        }
        function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
        }
        // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
        bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
        /**
         * @dev Storage slot with the address of the current implementation.
         * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
        /**
         * @dev Emitted when the implementation is upgraded.
         */
        event Upgraded(address indexed implementation);
        /**
         * @dev Returns the current implementation address.
         */
        function _getImplementation() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 implementation slot.
         */
        function _setImplementation(address newImplementation) private {
            require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
            StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
        }
        /**
         * @dev Perform implementation upgrade
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeTo(address newImplementation) internal {
            _setImplementation(newImplementation);
            emit Upgraded(newImplementation);
        }
        /**
         * @dev Perform implementation upgrade with additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCall(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            _upgradeTo(newImplementation);
            if (data.length > 0 || forceCall) {
                _functionDelegateCall(newImplementation, data);
            }
        }
        /**
         * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
         *
         * Emits an {Upgraded} event.
         */
        function _upgradeToAndCallUUPS(
            address newImplementation,
            bytes memory data,
            bool forceCall
        ) internal {
            // Upgrades from old implementations will perform a rollback test. This test requires the new
            // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
            // this special case will break upgrade paths from old UUPS implementation to new ones.
            if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                _setImplementation(newImplementation);
            } else {
                try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                    require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                } catch {
                    revert("ERC1967Upgrade: new implementation is not UUPS");
                }
                _upgradeToAndCall(newImplementation, data, forceCall);
            }
        }
        /**
         * @dev Storage slot with the admin of the contract.
         * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
         * validated in the constructor.
         */
        bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
        /**
         * @dev Emitted when the admin account has changed.
         */
        event AdminChanged(address previousAdmin, address newAdmin);
        /**
         * @dev Returns the current admin.
         */
        function _getAdmin() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
        }
        /**
         * @dev Stores a new address in the EIP1967 admin slot.
         */
        function _setAdmin(address newAdmin) private {
            require(newAdmin != address(0), "ERC1967: new admin is the zero address");
            StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
        }
        /**
         * @dev Changes the admin of the proxy.
         *
         * Emits an {AdminChanged} event.
         */
        function _changeAdmin(address newAdmin) internal {
            emit AdminChanged(_getAdmin(), newAdmin);
            _setAdmin(newAdmin);
        }
        /**
         * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
         * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
         */
        bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
        /**
         * @dev Emitted when the beacon is upgraded.
         */
        event BeaconUpgraded(address indexed beacon);
        /**
         * @dev Returns the current beacon.
         */
        function _getBeacon() internal view returns (address) {
            return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
        }
        /**
         * @dev Stores a new beacon in the EIP1967 beacon slot.
         */
        function _setBeacon(address newBeacon) private {
            require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
            require(
                AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                "ERC1967: beacon implementation is not a contract"
            );
            StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
        }
        /**
         * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
         * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
         *
         * Emits a {BeaconUpgraded} event.
         */
        function _upgradeBeaconToAndCall(
            address newBeacon,
            bytes memory data,
            bool forceCall
        ) internal {
            _setBeacon(newBeacon);
            emit BeaconUpgraded(newBeacon);
            if (data.length > 0 || forceCall) {
                _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
            }
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a delegate call.
         *
         * _Available since v3.4._
         */
        function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
            require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
            // solhint-disable-next-line avoid-low-level-calls
            (bool success, bytes memory returndata) = target.delegatecall(data);
            return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
        }
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.1) (proxy/utils/Initializable.sol)
    pragma solidity ^0.8.2;
    import "../../utils/AddressUpgradeable.sol";
    /**
     * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
     * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
     * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
     * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
     *
     * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
     * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
     * case an upgrade adds a module that needs to be initialized.
     *
     * For example:
     *
     * [.hljs-theme-light.nopadding]
     * ```
     * contract MyToken is ERC20Upgradeable {
     *     function initialize() initializer public {
     *         __ERC20_init("MyToken", "MTK");
     *     }
     * }
     * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
     *     function initializeV2() reinitializer(2) public {
     *         __ERC20Permit_init("MyToken");
     *     }
     * }
     * ```
     *
     * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
     * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
     *
     * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
     * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
     *
     * [CAUTION]
     * ====
     * Avoid leaving a contract uninitialized.
     *
     * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
     * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
     * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
     *
     * [.hljs-theme-light.nopadding]
     * ```
     * /// @custom:oz-upgrades-unsafe-allow constructor
     * constructor() {
     *     _disableInitializers();
     * }
     * ```
     * ====
     */
    abstract contract Initializable {
        /**
         * @dev Indicates that the contract has been initialized.
         * @custom:oz-retyped-from bool
         */
        uint8 private _initialized;
        /**
         * @dev Indicates that the contract is in the process of being initialized.
         */
        bool private _initializing;
        /**
         * @dev Triggered when the contract has been initialized or reinitialized.
         */
        event Initialized(uint8 version);
        /**
         * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
         * `onlyInitializing` functions can be used to initialize parent contracts.
         *
         * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
         * constructor.
         *
         * Emits an {Initialized} event.
         */
        modifier initializer() {
            bool isTopLevelCall = !_initializing;
            require(
                (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                "Initializable: contract is already initialized"
            );
            _initialized = 1;
            if (isTopLevelCall) {
                _initializing = true;
            }
            _;
            if (isTopLevelCall) {
                _initializing = false;
                emit Initialized(1);
            }
        }
        /**
         * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
         * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
         * used to initialize parent contracts.
         *
         * A reinitializer may be used after the original initialization step. This is essential to configure modules that
         * are added through upgrades and that require initialization.
         *
         * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
         * cannot be nested. If one is invoked in the context of another, execution will revert.
         *
         * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
         * a contract, executing them in the right order is up to the developer or operator.
         *
         * WARNING: setting the version to 255 will prevent any future reinitialization.
         *
         * Emits an {Initialized} event.
         */
        modifier reinitializer(uint8 version) {
            require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
            _initialized = version;
            _initializing = true;
            _;
            _initializing = false;
            emit Initialized(version);
        }
        /**
         * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
         * {initializer} and {reinitializer} modifiers, directly or indirectly.
         */
        modifier onlyInitializing() {
            require(_initializing, "Initializable: contract is not initializing");
            _;
        }
        /**
         * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
         * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
         * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
         * through proxies.
         *
         * Emits an {Initialized} event the first time it is successfully executed.
         */
        function _disableInitializers() internal virtual {
            require(!_initializing, "Initializable: contract is initializing");
            if (_initialized < type(uint8).max) {
                _initialized = type(uint8).max;
                emit Initialized(type(uint8).max);
            }
        }
        /**
         * @dev Returns the highest version that has been initialized. See {reinitializer}.
         */
        function _getInitializedVersion() internal view returns (uint8) {
            return _initialized;
        }
        /**
         * @dev Returns `true` if the contract is currently initializing. See {onlyInitializing}.
         */
        function _isInitializing() internal view returns (bool) {
            return _initializing;
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
    pragma solidity ^0.8.0;
    import "../proxy/utils/Initializable.sol";
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract ContextUpgradeable is Initializable {
        function __Context_init() internal onlyInitializing {
        }
        function __Context_init_unchained() internal onlyInitializing {
        }
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
        /**
         * @dev This empty reserved space is put in place to allow future versions to add new
         * variables without shifting down storage in the inheritance chain.
         * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
         */
        uint256[50] private __gap;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)
    pragma solidity ^0.8.0;
    import "./math/MathUpgradeable.sol";
    /**
     * @dev String operations.
     */
    library StringsUpgradeable {
        bytes16 private constant _SYMBOLS = "0123456789abcdef";
        uint8 private constant _ADDRESS_LENGTH = 20;
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            unchecked {
                uint256 length = MathUpgradeable.log10(value) + 1;
                string memory buffer = new string(length);
                uint256 ptr;
                /// @solidity memory-safe-assembly
                assembly {
                    ptr := add(buffer, add(32, length))
                }
                while (true) {
                    ptr--;
                    /// @solidity memory-safe-assembly
                    assembly {
                        mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                    }
                    value /= 10;
                    if (value == 0) break;
                }
                return buffer;
            }
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            unchecked {
                return toHexString(value, MathUpgradeable.log256(value) + 1);
            }
        }
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = _SYMBOLS[value & 0xf];
                value >>= 4;
            }
            require(value == 0, "Strings: hex length insufficient");
            return string(buffer);
        }
        /**
         * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
         */
        function toHexString(address addr) internal pure returns (string memory) {
            return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
        }
    }
    // SPDX-License-Identifier: MIT
    pragma solidity 0.8.13;
    import "./ILiquidityPool.sol";
    interface IStakingManager {
        struct DepositData {
            bytes publicKey;
            bytes signature;
            bytes32 depositDataRoot;
            string ipfsHashForEncryptedValidatorKey;
        }
        struct StakerInfo {
            address staker;
            ILiquidityPool.SourceOfFunds sourceOfFund;
        }
        function bidIdToStaker(uint256 id) external view returns (address);
        function getEtherFiNodeBeacon() external view returns (address);
        function initialize(address _auctionAddress, address _depositContractAddress) external;
        function setEtherFiNodesManagerAddress(address _managerAddress) external;
        function setLiquidityPoolAddress(address _liquidityPoolAddress) external;
        function batchDepositWithBidIds(uint256[] calldata _candidateBidIds, address _staker, ILiquidityPool.SourceOfFunds source, bool _enableRestaking) external payable returns (uint256[] memory);
        function batchDepositWithBidIds(uint256[] calldata _candidateBidIds, bool _enableRestaking) external payable returns (uint256[] memory);
        function batchRegisterValidators(bytes32 _depositRoot, uint256[] calldata _validatorId, DepositData[] calldata _depositData) external;
        function batchRegisterValidators(bytes32 _depositRoot, uint256[] calldata _validatorId, address _bNftRecipient, address _tNftRecipient, DepositData[] calldata _depositData, address _user) external;
        function batchApproveRegistration(uint256[] memory _validatorId, bytes[] calldata _pubKey, bytes[] calldata _signature, bytes32[] calldata _depositDataRootApproval) external;
        function batchCancelDeposit(uint256[] calldata _validatorIds) external;
        function batchCancelDepositAsBnftHolder(uint256[] calldata _validatorIds, address _caller) external;
        function updateAdmin(address _address, bool _isAdmin) external;
        function pauseContract() external;
        function unPauseContract() external;
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev This is the interface that {BeaconProxy} expects of its beacon.
     */
    interface IBeaconUpgradeable {
        /**
         * @dev Must return an address that can be used as a delegate call target.
         *
         * {BeaconProxy} will check that this address is a contract.
         */
        function implementation() external view returns (address);
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
    pragma solidity ^0.8.1;
    /**
     * @dev Collection of functions related to the address type
     */
    library AddressUpgradeable {
        /**
         * @dev Returns true if `account` is a contract.
         *
         * [IMPORTANT]
         * ====
         * It is unsafe to assume that an address for which this function returns
         * false is an externally-owned account (EOA) and not a contract.
         *
         * Among others, `isContract` will return false for the following
         * types of addresses:
         *
         *  - an externally-owned account
         *  - a contract in construction
         *  - an address where a contract will be created
         *  - an address where a contract lived, but was destroyed
         * ====
         *
         * [IMPORTANT]
         * ====
         * You shouldn't rely on `isContract` to protect against flash loan attacks!
         *
         * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
         * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
         * constructor.
         * ====
         */
        function isContract(address account) internal view returns (bool) {
            // This method relies on extcodesize/address.code.length, which returns 0
            // for contracts in construction, since the code is only stored at the end
            // of the constructor execution.
            return account.code.length > 0;
        }
        /**
         * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
         * `recipient`, forwarding all available gas and reverting on errors.
         *
         * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
         * of certain opcodes, possibly making contracts go over the 2300 gas limit
         * imposed by `transfer`, making them unable to receive funds via
         * `transfer`. {sendValue} removes this limitation.
         *
         * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
         *
         * IMPORTANT: because control is transferred to `recipient`, care must be
         * taken to not create reentrancy vulnerabilities. Consider using
         * {ReentrancyGuard} or the
         * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
         */
        function sendValue(address payable recipient, uint256 amount) internal {
            require(address(this).balance >= amount, "Address: insufficient balance");
            (bool success, ) = recipient.call{value: amount}("");
            require(success, "Address: unable to send value, recipient may have reverted");
        }
        /**
         * @dev Performs a Solidity function call using a low level `call`. A
         * plain `call` is an unsafe replacement for a function call: use this
         * function instead.
         *
         * If `target` reverts with a revert reason, it is bubbled up by this
         * function (like regular Solidity function calls).
         *
         * Returns the raw returned data. To convert to the expected return value,
         * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
         *
         * Requirements:
         *
         * - `target` must be a contract.
         * - calling `target` with `data` must not revert.
         *
         * _Available since v3.1._
         */
        function functionCall(address target, bytes memory data) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, "Address: low-level call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
         * `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, 0, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but also transferring `value` wei to `target`.
         *
         * Requirements:
         *
         * - the calling contract must have an ETH balance of at least `value`.
         * - the called Solidity function must be `payable`.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value
        ) internal returns (bytes memory) {
            return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
        }
        /**
         * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
         * with `errorMessage` as a fallback revert reason when `target` reverts.
         *
         * _Available since v3.1._
         */
        function functionCallWithValue(
            address target,
            bytes memory data,
            uint256 value,
            string memory errorMessage
        ) internal returns (bytes memory) {
            require(address(this).balance >= value, "Address: insufficient balance for call");
            (bool success, bytes memory returndata) = target.call{value: value}(data);
            return verifyCallResultFromTarget(target, success, returndata, errorMessage);
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
            return functionStaticCall(target, data, "Address: low-level static call failed");
        }
        /**
         * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
         * but performing a static call.
         *
         * _Available since v3.3._
         */
        function functionStaticCall(
            address target,
            bytes memory data,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            (bool success, bytes memory returndata) = target.staticcall(data);
            return verifyCallResultFromTarget(target, success, returndata, errorMessage);
        }
        /**
         * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
         * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
         *
         * _Available since v4.8._
         */
        function verifyCallResultFromTarget(
            address target,
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal view returns (bytes memory) {
            if (success) {
                if (returndata.length == 0) {
                    // only check isContract if the call was successful and the return data is empty
                    // otherwise we already know that it was a contract
                    require(isContract(target), "Address: call to non-contract");
                }
                return returndata;
            } else {
                _revert(returndata, errorMessage);
            }
        }
        /**
         * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
         * revert reason or using the provided one.
         *
         * _Available since v4.3._
         */
        function verifyCallResult(
            bool success,
            bytes memory returndata,
            string memory errorMessage
        ) internal pure returns (bytes memory) {
            if (success) {
                return returndata;
            } else {
                _revert(returndata, errorMessage);
            }
        }
        function _revert(bytes memory returndata, string memory errorMessage) private pure {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly
                /// @solidity memory-safe-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Library for reading and writing primitive types to specific storage slots.
     *
     * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
     * This library helps with reading and writing to such slots without the need for inline assembly.
     *
     * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
     *
     * Example usage to set ERC1967 implementation slot:
     * ```
     * contract ERC1967 {
     *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
     *
     *     function _getImplementation() internal view returns (address) {
     *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
     *     }
     *
     *     function _setImplementation(address newImplementation) internal {
     *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
     *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
     *     }
     * }
     * ```
     *
     * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
     */
    library StorageSlotUpgradeable {
        struct AddressSlot {
            address value;
        }
        struct BooleanSlot {
            bool value;
        }
        struct Bytes32Slot {
            bytes32 value;
        }
        struct Uint256Slot {
            uint256 value;
        }
        /**
         * @dev Returns an `AddressSlot` with member `value` located at `slot`.
         */
        function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
         */
        function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
         */
        function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
        /**
         * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
         */
        function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
            /// @solidity memory-safe-assembly
            assembly {
                r.slot := slot
            }
        }
    }
    // SPDX-License-Identifier: MIT
    // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)
    pragma solidity ^0.8.0;
    /**
     * @dev Standard math utilities missing in the Solidity language.
     */
    library MathUpgradeable {
        enum Rounding {
            Down, // Toward negative infinity
            Up, // Toward infinity
            Zero // Toward zero
        }
        /**
         * @dev Returns the largest of two numbers.
         */
        function max(uint256 a, uint256 b) internal pure returns (uint256) {
            return a > b ? a : b;
        }
        /**
         * @dev Returns the smallest of two numbers.
         */
        function min(uint256 a, uint256 b) internal pure returns (uint256) {
            return a < b ? a : b;
        }
        /**
         * @dev Returns the average of two numbers. The result is rounded towards
         * zero.
         */
        function average(uint256 a, uint256 b) internal pure returns (uint256) {
            // (a + b) / 2 can overflow.
            return (a & b) + (a ^ b) / 2;
        }
        /**
         * @dev Returns the ceiling of the division of two numbers.
         *
         * This differs from standard division with `/` in that it rounds up instead
         * of rounding down.
         */
        function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
            // (a + b - 1) / b can overflow on addition, so we distribute.
            return a == 0 ? 0 : (a - 1) / b + 1;
        }
        /**
         * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
         * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
         * with further edits by Uniswap Labs also under MIT license.
         */
        function mulDiv(
            uint256 x,
            uint256 y,
            uint256 denominator
        ) internal pure returns (uint256 result) {
            unchecked {
                // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                // variables such that product = prod1 * 2^256 + prod0.
                uint256 prod0; // Least significant 256 bits of the product
                uint256 prod1; // Most significant 256 bits of the product
                assembly {
                    let mm := mulmod(x, y, not(0))
                    prod0 := mul(x, y)
                    prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                }
                // Handle non-overflow cases, 256 by 256 division.
                if (prod1 == 0) {
                    return prod0 / denominator;
                }
                // Make sure the result is less than 2^256. Also prevents denominator == 0.
                require(denominator > prod1);
                ///////////////////////////////////////////////
                // 512 by 256 division.
                ///////////////////////////////////////////////
                // Make division exact by subtracting the remainder from [prod1 prod0].
                uint256 remainder;
                assembly {
                    // Compute remainder using mulmod.
                    remainder := mulmod(x, y, denominator)
                    // Subtract 256 bit number from 512 bit number.
                    prod1 := sub(prod1, gt(remainder, prod0))
                    prod0 := sub(prod0, remainder)
                }
                // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                // See https://cs.stackexchange.com/q/138556/92363.
                // Does not overflow because the denominator cannot be zero at this stage in the function.
                uint256 twos = denominator & (~denominator + 1);
                assembly {
                    // Divide denominator by twos.
                    denominator := div(denominator, twos)
                    // Divide [prod1 prod0] by twos.
                    prod0 := div(prod0, twos)
                    // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                    twos := add(div(sub(0, twos), twos), 1)
                }
                // Shift in bits from prod1 into prod0.
                prod0 |= prod1 * twos;
                // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                // four bits. That is, denominator * inv = 1 mod 2^4.
                uint256 inverse = (3 * denominator) ^ 2;
                // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                // in modular arithmetic, doubling the correct bits in each step.
                inverse *= 2 - denominator * inverse; // inverse mod 2^8
                inverse *= 2 - denominator * inverse; // inverse mod 2^16
                inverse *= 2 - denominator * inverse; // inverse mod 2^32
                inverse *= 2 - denominator * inverse; // inverse mod 2^64
                inverse *= 2 - denominator * inverse; // inverse mod 2^128
                inverse *= 2 - denominator * inverse; // inverse mod 2^256
                // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                // is no longer required.
                result = prod0 * inverse;
                return result;
            }
        }
        /**
         * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
         */
        function mulDiv(
            uint256 x,
            uint256 y,
            uint256 denominator,
            Rounding rounding
        ) internal pure returns (uint256) {
            uint256 result = mulDiv(x, y, denominator);
            if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                result += 1;
            }
            return result;
        }
        /**
         * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
         *
         * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
         */
        function sqrt(uint256 a) internal pure returns (uint256) {
            if (a == 0) {
                return 0;
            }
            // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
            //
            // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
            // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
            //
            // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
            // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
            // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
            //
            // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
            uint256 result = 1 << (log2(a) >> 1);
            // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
            // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
            // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
            // into the expected uint128 result.
            unchecked {
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                result = (result + a / result) >> 1;
                return min(result, a / result);
            }
        }
        /**
         * @notice Calculates sqrt(a), following the selected rounding direction.
         */
        function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = sqrt(a);
                return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
            }
        }
        /**
         * @dev Return the log in base 2, rounded down, of a positive value.
         * Returns 0 if given 0.
         */
        function log2(uint256 value) internal pure returns (uint256) {
            uint256 result = 0;
            unchecked {
                if (value >> 128 > 0) {
                    value >>= 128;
                    result += 128;
                }
                if (value >> 64 > 0) {
                    value >>= 64;
                    result += 64;
                }
                if (value >> 32 > 0) {
                    value >>= 32;
                    result += 32;
                }
                if (value >> 16 > 0) {
                    value >>= 16;
                    result += 16;
                }
                if (value >> 8 > 0) {
                    value >>= 8;
                    result += 8;
                }
                if (value >> 4 > 0) {
                    value >>= 4;
                    result += 4;
                }
                if (value >> 2 > 0) {
                    value >>= 2;
                    result += 2;
                }
                if (value >> 1 > 0) {
                    result += 1;
                }
            }
            return result;
        }
        /**
         * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log2(value);
                return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
            }
        }
        /**
         * @dev Return the log in base 10, rounded down, of a positive value.
         * Returns 0 if given 0.
         */
        function log10(uint256 value) internal pure returns (uint256) {
            uint256 result = 0;
            unchecked {
                if (value >= 10**64) {
                    value /= 10**64;
                    result += 64;
                }
                if (value >= 10**32) {
                    value /= 10**32;
                    result += 32;
                }
                if (value >= 10**16) {
                    value /= 10**16;
                    result += 16;
                }
                if (value >= 10**8) {
                    value /= 10**8;
                    result += 8;
                }
                if (value >= 10**4) {
                    value /= 10**4;
                    result += 4;
                }
                if (value >= 10**2) {
                    value /= 10**2;
                    result += 2;
                }
                if (value >= 10**1) {
                    result += 1;
                }
            }
            return result;
        }
        /**
         * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log10(value);
                return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
            }
        }
        /**
         * @dev Return the log in base 256, rounded down, of a positive value.
         * Returns 0 if given 0.
         *
         * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
         */
        function log256(uint256 value) internal pure returns (uint256) {
            uint256 result = 0;
            unchecked {
                if (value >> 128 > 0) {
                    value >>= 128;
                    result += 16;
                }
                if (value >> 64 > 0) {
                    value >>= 64;
                    result += 8;
                }
                if (value >> 32 > 0) {
                    value >>= 32;
                    result += 4;
                }
                if (value >> 16 > 0) {
                    value >>= 16;
                    result += 2;
                }
                if (value >> 8 > 0) {
                    result += 1;
                }
            }
            return result;
        }
        /**
         * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log256(value);
                return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
            }
        }
    }